The mild winter (so far) means that my backyard bird feeders have seen very little activity. We have the usual suspects visiting on a semi-regular basis: nuthatches, goldfinches, sparrows, house finches, downy woodpeckers, cardinals, chickadees, etc.. The most exotic birds to visit the feeders have been a pair of Pine Siskins - which seem to be rare in the state right now.
The most dedicated visitor to our feeders?
We have a group of three to five (or more) Fox Squirrels that spend a lot of time depleting our supply of sunflower seeds. I don't worry too much about them. They need to eat just like the birds and so far we have only bought a single bag of sunflower seeds this season.